Letter: Current account
Wednesday 12 August 1998
All wiring offers some resistance to the passage of current, and thus some power is lost in just pushing current to where it is wanted. The amount of power lost in this way depends on the square of the current, and so for a given amount of power to be delivered, the power lost in 6-volt transmission is 1,600 times that of 240-volt transmission. For that reason, 6-volt power supplies have to be produced by transforming down from mains voltage immediately adjacent to where they are needed.
Film The critics but sneer but these unfashionable festive films are our favourites
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Arts & Ents blogs
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- 2 Christmas comes early to Hong Kong, as millions of bank notes spill out onto busy street
- 3 Antonio Martin shooting: Police and protesters clash over teenager's death just five miles from Ferguson, Missouri
- 4 Northern Lights above Britain: Stunning Aurora Borealis illuminates Northumberland sky on Christmas Eve
- 5 British actor Idris Elba cannot star as James Bond because he is black, says shock jock Rush Limbaugh
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The Interview is finally released after Sony hack and terror threats – but reviews of North Korea satire are mixed
Christmas TV guide 2014: The best shows to watch from Doctor Who to Downton Abbey
Nigel Farage defends Kerry Smith 'ch***y' comment: 'If you are going for a Chinese, what do you say you’re going for?'
British actor Idris Elba cannot star as James Bond because he is black, says shock jock Rush Limbaugh
Rozanne Duncan: Ukip expels councillor for 'jaw-dropping' comments made in BBC TV interview
Germany anti-Islam protests: 17,000 march on Dresden against 'Islamification of the West'
Ukip member gets into Christmas spirit with Union Flag plea to Santa 'for our country back'
Panic Saturday: 13 million Britons spend £1.2bn – while 13 million others across the country live in poverty unable to afford food